Question

Plant Structure – internal and external

1) You are given part of a plant that was dug up in the garden that might be a horizontal root or a horizontal stem. Explain how you would tell which it is. Consider both external morphology and internal anatomy.

2) You look in a microscope and see a root with a root hair or a branch root. Explain how you could identify whether it is a root hair or a branch root.

3) Can you think of advantages to a plant of having the vascular bundles in a stem be around the outside, while the vascular tissue of the root is concentrated in the center?

4) What is the difference between a tissue system, a tissue, and a cell type? Give an example of each.

Answer 1

Answer-1:

If a plant part that had been dug looks like a swollon structure then it could either be a rhizome, bulb, tuber, etc. As far as horizontal stem is considered, it would be a rhizome because they always grow horizontally inside the ground.

Secondly, while looking at the root structure, usually, the horizontal roots always arises from the tap root system, in which a central root gives rise to many secondary horizontal root.

Answer-2:

Under the microscope, root hair and branch root can be easily distinguished from each other. Root hair are unicellular, which are the extensions of the root epidermis cell whose function is to increase the surface area for absorption. whereas, branch root is multicellular and can be clearly demarcated with the presence of vascular tissues, epidermis, cortex and endodermis.